1. Field of the Invention
The present invention relates to a semiconductor light emitting device having a plurality of light emitting sections.
2. Related Art
There has been proposed a semiconductor light emitting device in which in order to increase light emission intensity, a plurality of light emitting sections are vertically and horizontally arranged on a substrate, and light is taken out from the direction of the substrate surface opposite to the surface on which the light emitting sections are arranged The intensity of light taken out to the light taking-out surface side can be further increased by devising the shape of light emitting section or increasing the number of light emitting sections arranged on the substrate.
In the semiconductor light emitting device of this type, electrodes are provided on both sides of the substrate. However, since the electrode material is generally opaque, there is a problem that light is shielded by the electrodes, and thereby the intensity of light is lowered.
In order to solve this problem, it is conceivable, for example, to reduce the electrode area with respect to the area of the light emitting section. However, in this case, the current flowing through the light emitting section is also limited, as a result of which the light emission intensity is also lowered. On the other hand, it is also possible to use transparent electrodes made of ITO (Indium Tin Oxide) or the like, as the electrode material. However, a transparent electrode in general has a large resistance to cause a voltage drop, as a result of which the light emission intensity of the light emitting section also cannot be improved.
On the other hand, there is proposed a semiconductor light emitting device in which by forming grooves with inclined side surfaces by using a V-shaped dicing blade, the quantity of emitted light proceeding toward an electrode on the light emitting surface from positions opposite to the electrode on the light emitting surface is substantially reduced, thereby increasing the quantity of light incident on the light emitting surface except portions at which the electrode is formed (Japanese Patent No. 3312049, paragraphs 0073 to 0075, FIG. 13).
In the patent document 1, the electrode on the light emitting surface and the groove formed by using the dicing blade are arranged opposite to one another. However, the light intensity on the light emitting surface is to be varied depending upon the kind of light emitting section. Thus, in the case where the electrode is arranged at a place where the light intensity is originally high, even when the groove formed by using the dicing blade is arranged opposite to the electrode, the light emission efficiency may not be improved so much.